Miniature relay



May 8, 1956 J. A. ROMER 2,744,978

MINIATURE RELAY Filed April 17, 1952 3 Sheets-Sheet 2 IN VEN TOR.

y 8, 1956 J. A ROMER 2,744,978

MINIATURE RELAY Filed April 17, 1952 3 Sheets-Sheet 3 21' .9 V 47 6 T fl 26 12 Z I J! IN VEN TOR.

( azz ga am Fame/1' United States Patent 4 O MINIATURE RELAY Jan Adam Romer, Princeton, Ind., assignor to Potter & Brumfield, Princeton, Ind., a corporation of Indiana Application April 17, 1952, Serial No. 282,826

4 Claims. (Cl. 200-87) The present invention relates to relays, and more particularly to certain constructional features of a miniature relay.

More recently there has been a need for small compact relays which have been classified as miniature relays. In designing a relay of small size, adequate sensitivity and reliable operation in spite of high gravitational forces, many factors not expected probably are encountered as contrasted to the manufacture of conventional sized relays. The sensitivity must not drop and the tolerances in dimensions are a great deal smaller because of the over all reduction in size of the relay. Accordingly certain changes in construction are deemed necessary. Such changes, however, must not be subject to excessive increase in manufacturing costs.

In accordance with the present invention it is proposed to overcome the problems encountered in designing a small or miniature relay, which for example might have a one-half inch diameter solenoid, by utilizing an improved structure wherein a molded coil spool is provided which supports the pole piece, armature supports and certain terminals and contacts of an electric circuit.

It is, therefore, an object of the present invention to provide an improved miniature relay structure which is simple and economical to manufacture.

Another object of the invention is to provide an improved miniature relay having a molded spool structure which carries the pole piece, armature support, and contact members.

Still another object of the invention is to provide in a miniature relay an improved balanced armature and method of assembly.

A still further object of the invention is to provide an improved relay structure whereby the armature support is carried by the molded spool structure.

Other and further objects of the invention subsequently will become apparent by reference to the following description taken in conjunction with the accompanying drawings, wherein:

Figure 1 is a side view of the basic support assembly for relay construction in accordance with the present invention; I

Figure 2 is an end or bottom view of the support structure shown in Figure 1;

Figure 3 is a longitudinal cross section view of the support assembly of Figure 1;

Figure 4 is a partial view as seen in the direction of the arrows along the line 4-4 of Figure 3;

Figure 5 is a detailed view of one component of the re lay structure;

Figure 6 is a side view of a completed relay assembly with one armature support partially broken away;

Figure 7 is an end or bottom view of the relay assembly shown in Figure 6; v

Figure 8 is a detailed view as seen in the direction of the arrows along the line 8-8 of Figure 7;

Figure 9 is a side view of another embodiment similar to that shown in Figure 1;

Figure 10 is an end or bottom view of the embodiment shown in Figure 9; and

2,744,978 Patented May 8, 1956 Figure 11 is a detailed plan view of one of the elements used in the devices shown in Figures 9 and 10.

Referring to Figures 1, 2, 3 and 4 of the drawing it will be noted that there has been shown a relay structure which has a molded spool 11 provided at one end with a narrow flange 12 and at the other end with an enlarged flange 13. The enlarged flange 13 carries a pair of armature bearing supports 14 and several contact terminals 15 and 16 adapted to receive or support contacts. The enlarged flange 13 of the molded spool 11 also carries partially embedded a pole piece 17. Extending through the center of the spool 11 is a cylindrical magnetic core member 19 having at its lower end a reduced diameter portion 21 which preferably is riveted to the pole piece 17. The magnetic core 19 is provided at its opposite end with an other reduced diameter portion 22 the purpose of which subsequently will become apparent. From Figure 4 it will be noted that the electric terminal 15 which is partially embedded in the enlarged flange 13 of the spool 11 carries an electrical contact 23 which is suitably riveted to the terminal 15.

The structure thus far described and shown in Figures 1 through 4 is the basic structure for a miniature relay wherein the flanges of the spool may have a diameter in the order of one-half inch. In view of the small size of the structure it will be appreciated that conventional modes of construction are not applicable since they would introduce too much variation. The structure shown in these figures is then placed on a winding machine for the formation of the actuating coil of the relay. Thereafter the remaining parts of the relay are assembled.

By referring to Figures 5, 6, 7 and 8 it Will be noted that a coil 24 has been wound on the spool 11. Partially shielding the coil 24 is a magnetic member 25 which is provided with a suitable aperture for receiving the reduced diameter portion 22 of the core 19. The projecting end of the core member 22 is riveted to the member 25 which has an arcuate portion 26. It will be noted that the arcuate portion 26 is concentric to the arcuate outer surface of the pole piece 17.

The armature bearing member 14 carries adjustable bearing members 27 and 28 to support the armature pin 29. The armature pin 29 is connected to an armature of balanced construction having a segmental portion 31, a narrow intermediate portion 32 which has an elongated slot 33 and contact carrying portion 34. The contact carrying portion 34 carries a contact 35 which is riveted thereto and supports another contact 36 which is adjustably supported in a bifurcated boss 37. A suitable spring 38 engages one of the bearing members 27 and the narrowed portion 32 of the balanced armature.

The narrowed portion 32 of the armature has an elongated slot 33 and the narrowed portions adjacent thereto have arcuate configurations 39 which have an inner radius slightly in excess of the radius of the bearing support pin 29. This clearance is specifically provided for an assembly operation whereby the armature segment 31 may be properly positioned with respect to the pole piece 17 and the arcuate shielded portion 26 so that an equal air gap may be obtained for maximum sensitivity and reliability in operation. When the armature thus has been positioned solder is introduced into the slot 33 to take up the clearance between the armature portions 39 and the pin 29. Thereafter the various contacts may be suitably adjusted for proper make and break operation. It will be noted that the terminal 16 is provided with an adjustable contact 41 for cooperation with the riveted contact 35 of 19,. the magnetic. shield 26,. the pole piece 17 and. the armature are all of magnetic material. The remaining elements are of non-magnetic material. This is mentioned since the bearing support members 14 are formed in a single piece as shown in- Figure 5. This piece is press fitted onto the core 19 and abuts the pole piece 17 which is riveted to the reduced diameter portion 21 of the core.

A further embodiment of the present invention is shown in Figures 9, I and 11. Those elements which are of identical shape and function corresponding to elements in the previously described and illustrated figures of patent drawing have been given similar reference characters in Figures 9 and 10. Those elements which have been modified slightly have been giventhe same reference character plus the letter a.

Therefore, it will be noted-that in Figures 9, 10 and 11 the armature has been modified at 34a so that it no longer carries any contacts. The armature bearing support members 14a have been modified to receive a support platform 51 of a configuration similar to that shown in Figure 11. This'support platform is fitted by means of mortise joints and soldered into position. Suitably supported from the platform 51 is a contact 52 mounted on a movable contact spring or arm 53. The contact 52 is arranged to close a circuit with another contact 54 carried by a contact spring 55. The contact 52 is also arranged to control a circuit by engaging the contact 56 mounted upon a contact spring 57. Suitable insulator spacers 58 provide a proper spacing between the several springs and the platform support 51. The spaces 58 are held in position by'a plate 59 which is engaged by a screw 61 which passes through the threaded opening in the mounting plate 51. The screw 61 is suitably insulated from the springs 53, 55 and 57 by an insulator sleeve 62. The lower extremity of the screw 61 extends an appreciable distance beneath the support platform 51 and is engaged by a lock nut 63 which may be so positioned so as to properly limit the de-energized' portion of the armature 31 so as to provide the proper air gap between this member and the pole piece 17 and the shield26.

From Figure 10 it will be noted that the armature 34a carries an actuator 64' which is mounted by means of a reduced section 65 fitting into a suitable opening in the armature member 34a. The actuator member 64 engages the two springs 53 for the dual set of contacts corresponding' to those illustrated in Figure 9'. As may be seen from Figure I0 each of the contact springs 53, 55 and 57 in the two sets is provided with suitable solder lugs sothat circuit connections may be made to these members.

The embodiment of the type shown in Figures 9, 10

and 11 has a pole piece 17 and the two bearing support members 1422 partially embedded in the molded spodl flange 12. This construction, therefore, has the advantage of accurate spacing between the armature bearing support member 14 and the pole piece 17 and the magnetic shield 26. Thus any variation in manufacture is greatly minimized by this construction which is the same as the previously described construction in Figures 1 to 8; action of the platform 51 accurately mounted upon the bearing support members 14:: furthermore minimizes the possibility of variations which might or might otherwise change the operating characteristics of the relay. The adjustable nut 63 predetermines the maximum air gap between the pole piece and the armature, and hence. assures maintenance of the operating characteristics.

From the foregoing it isbeiievcd that it will be appreciatcd by those skilled in the art that the present construction departs radically from conventional relay embodiments and accordingly by means of the construction shown and described a highly reliable yet economical sensitive relay can be manufactured.

While for the purpose of describing and illustrating the principles of the present invention, a particular embodiment hasbeen shown in the drawing it is to be understood that the invention is not to be limited thereby since such The variations are contemplated in the embodiment. as may be commensurate with the spirit and scope of the invention set forth in the appended claims.

I claim as my invention:

1. A miniature relay comprising a cylindrical magnetic core carried by and bonded to a plastic spool having an enlarged end, said enlarged end carrying partially embedded contact terminals and armature bearing support members, a magnetic pole piece surrounding one end of said core and having an arcuate edge, amagnetic segment of a cylinder supported from the other end of said core and extending along said spool to the proximity of the arcuate edge of said magnetic pole piece, and an armature carried by said bearing support members having a magnetic circuit portion extending between said pole piece and said cylindrical segment, said armature. having a contact carrying portion cooperating with said contact terminals.

2. A miniature relay comprising a cylindrical magnetic core carried by and bonded to a plastic spool having an enlarged flange end, said enlarged end carrying partially embedded contact terminals and armature bearing support members, contacts carried by said terminals, a magnetic pole piece surrounding one end of said core and having an arcuate edge, a magnetic shield comprising a segment of a cylinder riveted to and supported from the other end of said core and extending along said spool to the proximity of the arcuate edge of said pole piece, and an armature carried by said bearing support members having a magnetic circuit portion extending in overlapping relation with respect to said pole piece andsaid cylindrical segment shield, and a contact carrying portion cooperating w'ith said first contacts.

3. A miniature relay comprising a magnetic core carried by and bonded to a plastic spool having an enlarged flange end, said end carrying partially embedded contact terminals and armature bearing support members, a magnetic pole piece surrounding one end of said core, said pole piece having an arcuate segment, a magnetic shield comprising a segment of a cylinder riveted to and supported from the other end of said core, said cylindrical segment extending along said spool to the proximity of said pole piece to form an arcuate magnetic gap, and an armature carriedby said bearing support members having a magnetic circuit portion comprising an arcuate segment extending in overlapping relation with respect to said pole piece and said' arcuate segment of said shield.

4. A miniature relay comprising a magnetic core carried by and bonded to a plastic spoolhaving an enlarged flange end, said end carrying partially embedded nonmagnetic armature bearing support members, a magnetic pole piece surrounding one end of said core, said pole piece havingan arcuate segment, a magnetic shield comprisingasegment of a cylinder riveted to and supported from the other end of said core, said cylindrical segment extending along said spool to the proximity of said pole piece to provide an arcuate air gap, an armature carried by said bearing support members having an arcuate segmental portion extending in overlapping. relation with respect to said pole piece and said arcuat'e segment of said shield, and a contact assembly supported from said armature bearing support members arranged to be acmated by said armature.

References Citedin the file of this-patent UNITED STATES PATENTS 

